The present invention relates to a radiation shield which is used for protecting workers from radiation exposure in a radiation environment.
In recent years, working under radiation, inclusive of safety, is generalized in accordance with laws and regulations in the fields of medical treatment, general industry and atomic plants, and satisfactory maintenance and inspection are conducted in various industries. Working in a radiation environment is indispensable to all industrial fields, and required measures are taken to reduce the radiation exposure of workers engaged in such working. As one measure, there is a method which uses a radiation shield such as that proposed in Japanese Utility Model Laid-Open No. 147998/1986. In this method, the attenuation characteristic of radiation which is attenuated by water serving as a shielding liquid is utilized, and equipment or apparatus which may emit radiation is covered with water-filled flexible bags made of synthetic resin cloth or rubber.
However, the radiation shield proposed in Japanese Utility Model Laid-Open No. 147998/1986 has the following practical disadvantages, and functional and practical improvements are needed in practical use.
Specifically, since the conventional radiation shield is used within the strength range of the bag, a reinforcement wall made of the same material as the bag is provided inside the bag, and if a bag is needed which has the thickness and strength required for a shielding effect which matches the size of a radiation source, a bag having a considerably large weight must be prepared. When in use, the bag may be deformed or damaged in spite of the reinforcement wall. It is, therefore, necessary to make structural improvements so as to increase the resistance of the bag to excessively large external forces and the like, and there is also room for improvements in handling, storage and the like.
Accordingly, a first object of the present invention is to provide a radiation shield having a shielding effect which achieves a satisfactory reduction in radiation exposure without causing deformation due to a increase in the weight of a bag due to variations in the weight, the shielding thickness and the like of the bag even if a change occurs in the conditions under which the radiation shield is used, unlike the above-described conventional radiation shield. In addition to the first object, a second object of the present invention is to provide a radiation shield with ease of handling and ease of storage.